JPS6363804A - Vibration damping apparatus in illumination pole - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION INDUSTRIAL APPLICATION J This invention relates to an allocating device for lighting poles consisting of cantilevered hollow poles installed mainly on elevated highways, bridges, etc.

``Prior Art'' Lighting poles l made of cantilevered hollow poles as shown in FIG. 3 are installed mainly on elevated highways, bridges, etc.

The lighting column l constantly vibrates due to external forces such as road vibrations caused by running vehicles or wind.

A result of the vibration measurement is as follows.

1) The natural frequency of the lighting column is approximately 1 to 2 Hz.

2) Most of the road surface vibrations caused by vehicle running are vertical components, and the predominant frequency appears in a wide band of 1 to 1411z.

3) The vibration at the tip of the lighting column is excited by road surface vibration regardless of the density of running vehicles, and has a predominant frequency that is almost the same as that on the road surface.

4) The same can be said for acceleration; the vertical direction is predominant on both the road surface and the tip of the lighting column, and for lighting columns with particularly severe vibration disturbances, the maximum acceleration in the vertical direction of the tip was recorded as gal exceeding the gravitational acceleration.

As a result, the above-mentioned vibration phenomenon causes inconveniences such as shortening the life of the lighting fixture 2 attached to the tip of the lighting column 1, or leading to accidents such as lamp burnout and shaking of the lighting.

Therefore, measures must be taken to attenuate the vibrations of the lighting column main body, and a control membrane device is added to the tip of the lighting column where vibrations are severe.

The allocation device must not be added in a manner that impairs the appearance of the lighting column, and must be housed in a hollow portion of a predetermined size and must not protrude outside the column.

A proposal that satisfies these requirements is the Special Publication Publication No. 41-127
There is No. 87.

In this device, one end of the buffer spring is attached to the vibrator, and the other end of the buffer spring is attached to the end of the casing having the vibrator contact portion, so that the casing can be easily attached to and removed from the hollow ball. The vibrator vibrates in the axial direction of the cylindrical casing and hits the abutting portion (Ii) at the end in the axial direction.

``Problems to be solved by the invention'' However, the vibration damping installation described above has the following problems.

i) Since the vibration absorption direction is defined in the axial direction of the housing and is biased, measures should be taken regarding the direction in which vibration should be suppressed based on the three dimensions of the lighting column, the roadbed structure, etc., and the vibration characteristics obtained from the measurement results described above. is insufficient, and a sufficient vibration damping effect cannot be obtained.

ii) Since it is a collision type, it may generate noise and cause pollution.

iii) Since it is a mechanical mechanism, regular maintenance is required.

``Means for Solving the Problems'' and ``Operations'' The present invention was made in view of the above circumstances, and its gist is that A high viscosity viscoelastic fluid with a viscosity of 1 poise or more or a kinematic viscosity of 100 cs or more or a viscous fluid is placed in a container that is fixed in the built-in container, and a steel ball with a diameter of about 10 m is added to the weight of the fluid. Assuming that 172 to 1/1 of the viscous fluid is enclosed, the synergistic effect of the internal viscous resistance of the viscoelastic fluid or the viscous fluid and the collision type damper effect between the steel balls absorbs and damps vibration energy with high efficiency, and also creates a fluid layer. It has a vibration damping effect in the three-dimensional direction of vibration frequency, which eliminates all of the problems mentioned above.

"Example" This will be explained in detail below based on the drawings.

FIGS. 1a and 1b are explanatory diagrams of a case in which a container according to the present invention is built into a hollow portion at the tip of a lighting column, and FIG. 2a is an explanatory diagram.

b is an explanatory diagram of a case where the lighting device is built into the upper half space of the lighting fixture.

The container 3 shown in FIG. 1a is normally a cylindrical container in order to make maximum use of the hollow portion at the tip of the illumination column 1, but it may have any shape as long as it can be built into the container. In addition, 5 in the figure indicates a conduit.

The container 3 is located in the hollow part 1a at the tip of the lighting column 1 as shown in figure b.
Built-in and fixed in (horizontal part).

A highly viscous viscoelastic fluid or viscous fluid 4 is sealed inside the container 3, and uses its internal viscous resistance to absorb vibrational energy in three-dimensional directions, ensuring the desired damping ability within a limited volume. In order to achieve this, in the present invention, the steel balls 6 are further enclosed, and in addition to the above-mentioned internal resistance, vibration energy is absorbed by the collision type damper effect between the steel balls and the damping effect is enhanced. ing.

As a result of experiments, it has been found that the viscosity of the fluid 4 to achieve a predetermined back-reducing ability is effective if it has a viscosity of 1 poise or more or a kinematic viscosity of 100 cs or more (values at 40° C.).

In addition, regarding the degree of filling in order to perform stirring motion and collision-type damper action in the container in order to produce a damping effect, the container is filled with 174 to 374 fluid 4, and the steel ball 6 with a diameter of about 10 fl is equal to the weight of the fluid 4. As a result of experiments, it was found that it was in the range of 1/'2 to 1/1 of .

A specific example of the fluid 4 is silicone oil.

There are CMC etc.

Incidentally, in order to increase the internal resistance, iron powder is mixed in, but this may be done if necessary.

The container 3'' shown in FIG. 2a is usually made into an oval shape to match the shape of the lighting fixture 2, and it is preferable to distribute heat shielding plates to avoid the heat generated by the lower lighting lamp (not shown). .

Enclosed fluid 4. Regarding the steel ball 6, the same applies to the case shown in Fig. 1.

FIG. 4 shows the results of a model experiment in which the damping effect of the fJi protruding damper action in the three-dimensional direction in the apparatus of the present invention was investigated.

"Effect of the invention" hmm The effects of the present invention described above are as follows.

i) Since the vibration absorption direction works in three dimensions, it can correspond to the vibration characteristics of the tip of the lighting column and can effectively suppress vibration.

ii) Since the vibration is absorbed by the 1-hour vibration inside or in the fluid, no sound is emitted and there is no concern about noise.

iii) No separate periodic maintenance is required for the container after it has been filled with fluid.

[Brief explanation of drawings]

1A and 1B are a front side view and an explanatory view of a built-in state of a container for incorporating the tip of a lighting column according to the present invention, and FIGS. 2A and 2B are a plan view and a front view of a container for incorporating a lighting lamp according to the present invention. FIG. 3 is an explanatory diagram of a lighting column targeted by the present invention, and FIG. 4 is an explanatory diagram of a damping effect test of the apparatus of the present invention. DESCRIPTION OF SYMBOLS 1... Lighting pillar, 2... Lighting fixture, 3... Container, 4... Viscous fluid, 5... Electric conduit, 6... Steel ball. Zugi 4 Akio, b. a, b.

Claims (1)

[Claims] The viscosity is 1 poise or more, or the kinematic viscosity is 1.
A viscoelastic fluid with a high viscosity of 00 cst or more or a viscous fluid is filled in 1/4 to 3/4 of the container, and a steel ball with a diameter of about 10 mm is sealed in 1/2 to 1/1 of the weight of the fluid. A vibration damping device for lighting pillars.